During the past 25 years most patients over 40 years of age having aortic valve replacement have had coronary angiography preoperatively. At least 33 studies have reported the frequency of significant (greater than 50% diameter reduction) coronary arterial narrowing in patients with valvular aortic stenosis and most of these reported studies included only the patients who had the stenotic valve replaced with a prosthesis or bioprosthesis (Table I). Patients with mitral valve dysfunction usually were excluded. Analysis of the studies, which unfortunately also included a small percent of patients less than 40 years of age, disclosed that 37% of the patients (1302 of 3509) had significant narrowing by angiogram of 1 or more major epicardial coronary arteries.